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(clojure.core/use 'clojure.core)

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myproject=> (File/separator)
CompilerException java.lang.RuntimeException: No such namespace: File, compiling:(NO_SOURCE_PATH:5) 
myproject=> (java.io.File/separator)
"/"
myproject=> 

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myproject=> (clojure.core/use 'clojure.core)
nil
myproject=> (import '(java.io InputStream File))
java.io.File

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(ns blog.explorandoclojure
	(:use blog.utils clojure.contrib.str-utils) (:import (java.io File)))

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public class Math {

  public static void Main(String[] args) {
    float raio = 75;
    System.out.println(areaCirculo(raio));
  }

  private static double areaCirculo(float raio) {
    return 3.14 * (raio * raio);
  }

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private static double areaCirculo(float raio) {
  if(raio == null)
    // NullPointerException
  return 3.14 * (raio * raio);
}

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public void doSomeThing(){
  Client client = service.findClientById("1103"); // Pode dar NPE
    if(client == null)
      // Faça alguma coisa.
    String name = client.getName(); // Ops, sem checar por null. NPE
}

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public static List<Double> squareList(List<Double> in){	
   List<Double> out = new ArrayList<Double>();

   for (Double d : in) 
      out.add(d*d);

   return out;	
}

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square :: [Double] -> [Double]

square (x:xs) = x*x : square xs
square [] = []

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import Test.QuickCheck
import Data.List

square :: [Double] -> [Double]
square (x:xs) = x*x : square xs
square [] = []

-- testing
prop_test1 xs = not(null xs)  ==> map(1*) ( square xs ) == map (\x -> x * x) xs